Jump to main content
Jump to site search

Issue 3, 2011
Previous Article Next Article

Metal-binding properties of Hpn from Helicobacter pylori and implications for the therapeutic activity of bismuth

Author affiliations

Abstract

Nickel is of particular importance to Helicobacter pylori in part because it acts as a cofactor of urease, which is critical to the survival of H. pylori. In this study the nickel storage, histidine-rich protein Hpn from H. pylori was converted into a Ni2+ probe by inserting it between two fluorescence resonance energy transfer (FRET) partners, cyan fluorescent protein (CFP) and yellow fluorescent protein (YFP). The resulting construct, Hpn-FRET, exhibited a change in FRET upon the binding of Ni2+. Hpn-FRET has a moderate selectivity for Ni2+; it also responds to Zn2+ and Co2+ but not to other biometals. Competition experiments between Ni2+ and other metals plus the measured Kd values for Zn2+ and Ni2+ establish the selectivity order for Hpn-FRET as Zn2+ > Ni2+ > Co2+ ≫ other biometals. Bismuth is widely used as a therapeutic agent against H. pylori, and Hpn has been suggested as one of the possible targets. The dissociation constant of Bi3+ to Hpn-FRET was measured to be 6.19 × 10−5 M. Further experiments using Hpn-FRET in E. coli indicate that Hpn-FRET responds to Bi3+ but not to Ni2+ and Zn2+ inside E. coli. The result shows that unlike Ni2+ and Zn2+, which are tightly regulated in most bacteria, available Bi3+ can reach high micromolar levels inside E. coli.

Graphical abstract: Metal-binding properties of Hpn from Helicobacter pylori and implications for the therapeutic activity of bismuth

Back to tab navigation
Please wait while Download options loads

Supplementary files

Publication details

The article was received on 04 Aug 2010, accepted on 15 Oct 2010 and first published on 16 Nov 2010


Article type: Edge Article
DOI: 10.1039/C0SC00411A
Citation: Chem. Sci., 2011,2, 451-456
  •   Request permissions

    Metal-binding properties of Hpn from Helicobacter pylori and implications for the therapeutic activity of bismuth

    S. V. Wegner, E. Ertem, M. Sunbul and C. He, Chem. Sci., 2011, 2, 451
    DOI: 10.1039/C0SC00411A

Search articles by author